namespace Avinash{    class Program    {        static void Main(string[] args) { SetListItemPermission(); } static void SetListItemPermission () { //Get SPWeb object SPSite Site = new SPSite("http://
    
     "); SPWeb Web = Site.OpenWeb(); //Get Role Definition SPRoleDefinition RoleDefinition = Web.RoleDefinitions.GetByType(SPRoleType.Administrator); //Get SPListItem SPList List = Web.Lists["
     
      "]; // Or you can use Web.GetList method for better performance SPListItem ListItem = List.Items[1]; //Create new Role Assignment SPRoleAssignment RoleAssignment = new SPRoleAssignment("
      
       ", "
       
        ", "
        
         ", ""); RoleAssignment.RoleDefinitionBindings.Add(RoleDefinition); //Break permission if necessary if(!ListItem.HasUniqueRoleAssignments) { ListItem.BreakRoleInheritance(true); } //Add Role Assignment to SPListItem's Role Assignment Collection ListItem.RoleAssignments.Add(RoleAssignment); ListItem.Update(); } } }